Project description:Genome-wide expression analysis of 6 batch cultivations of actinorhodin-producing wild type and recombinant strain of Streptomyces coelicolor
Project description:To identify unique gene expression in higher antibiotics producing Streptomyces coelicolor strain, non-producer M1146 and the derivative strain M1146+ACT (M1146 with actinorhodin biosynthetic genes cluster) was choosen for comparative transcriptome analysis. The genes with different gene expression might be key genes important for antibiotics production.
Project description:This project aims to discover novel bioactive compounds from Streptomyces isolated from the rhizosphere from wild medicinal plants from Hamedan province, Iran. Proteomics is used to assist in discovery and characterization of the compounds. Streptomyces isolates are grown on ISP-4 medium for three days, proteins were extracted and analysed by shotgun proteomics.
Project description:In this study, we describe the isolation and identification of Streptomyces isolates collected from traditional medicinal plants’ rhizosphere during a campaign in Hamedan Province, Iran. Traditional medicinal plants represent a rich and unique source for the isolation of Streptomyces and new antimicrobial compounds. This strain was isolated from the rhizosphere of Helichrysum rubicundum
Project description:In this work, we identified glucose and glycerol as tacrolimus repressing carbon sources in the important species Streptomyces tsukubaensis. A genome-wide analysis of the transcriptomic response to glucose and glycerol additions was performed using microarray technology. The transcriptional time series obtained allowed us to compare the transcriptomic profiling of S. tsukubaensis growing under tacrolimus producing and non-producing conditions. The analysis revealed important and different metabolic changes after the additions and a lack of transcriptional activation of the fkb cluster. In addition, we detected important differences in the transcriptional response to glucose between S. tsukubaensis and the model species Streptomyces coelicolor. A number of genes encoding key players of morphological and biochemical differentiation were strongly and permanently downregulated by the carbon sources. Finally, we identified several genes showing transcriptional profiles highly correlated to that of the tacrolimus biosynthetic pathway regulator FkbN that might be potential candidates for the improvement of tacrolimus production
Project description:Here, we address the transcriptional response to both novobiocin-induced rapid chromosome relaxation or long-term topological imbalance, both increased and decreased supercoiling, in environmental antibiotic-producing bacteria belonging to the Streptomyces genus.
Project description:Chitin is the second most abundant biopolymer present in soils and is utilized by antibiotic-producing Streptomyces species. Its monomer, N-acetylglucosamine (NAG), regulates the developmental program of the model organism Streptomyces coelicolor. NAG blocks differentiation when growing on rich medium whilst it promotes development on poor culture media. We report here the negative effect of NAG on tacrolimus (FK506) production in Streptomyces tsukubaensis NRRL 18488 growing on a defined rich medium. Using microarrays technology, we found that GlcNAc represses the transcription of fkbN, encoding the main transcriptional activator of the tacrolimus biosynthetic cluster, and of ppt1, encoding a phosphopantheteinyltransferase involved in tacrolimus biosynthesis. On the contrary, NAG stimulated transcription of genes related to amino acid and nucleotide biosynthesis, DNA replication, RNA translation, glycolysis, pyruvate metabolism, and key gene members of the PHO regulon. The results obtained support those previously reported for S. coelicolor, but some important differences were observed
Project description:Streptomyces bingchenggensis is a soil bacterium that produces a family of macrolide antibiotics, milbemycins, which is commercially important in crop protection, human and veterinary medicine. After the complete genome sequence, and annotation, for further development of our gene expression approach to biosynthesis, we have employed whole genome microarray expression profiling as a discovery platform to obtain improved specificity and sensitivity of gene expression analysis, allowing a global and at the same time detailed picture of how gene clusters for secondary metabolism are modulated. In the result, we confirmed the expression mil and nan gene cluster, furthermore, pks3, pks5 and nrps7, nrps8 also showed significant gene expression, but no obvious products detected. In Streptomyces bingchenggensis, there are also corresponding genes belonging to Defense mechanisms, which is much more than other Streptomyces, for the resistance of own metabolites and dealing with complex environmental factors.
Project description:Soil microbiota can confer fitness advantages to plants and increase crop resilience to drought and other abiotic stressors. However, there is little evidence on the mechanisms correlating a microbial trait with plant abiotic stress tolerance. Here, we report that a class of Streptomyces effectively alleviates the drought and salinity stress by producing new spiroketal polyketide pteridic acid H (1) and its isomer F (2). The bifunctional pteridic acid biosynthetic gene cluster (pta), which is also responsible for the biosynthesis of the known antimicrobial elaiophylin, was confirmed by bioinformatic analysis and in vivo CRISPR base editing. Pteridic acids H and F exhibited profound effects in promoting root growth in Arabidopsis at a concentration of 0.5 ng mL-1 (1.3 nM) under abiotic stress, indicating they are a new class of plant stress regulators. Phylogenetic and geographical distribution analysis revealed that the pta was mainly disseminated by vertical transmission and occasional horizontal gene transfer and is widely distributed in numerous Streptomyces in different environments. This discovery provides a new perspective for understanding plant-Streptomyces interactions and provides a novel, promising approach for utilising beneficial Streptomyces and their secondary metabolites in agriculture to mitigate the detrimental effects of climate change.
Project description:Bacterial genomic plasticity and instability carry multiple functional genetic information in Streptomyces secondary metabolism. Our previously publication has reported an effective industrial Streptomyces strain, with a unique phenotype of the high clavulanic acid yield. The complete genome of strain F163-1 harboring a 136.9-kb giant region of plasticity (RGP) was sequenced. The chromosome and plasmid are densely packed by an exceptionally huge variety of potential secondary metabolic gene clusters, excluding production of putative antibiotics. Intriguingly, architecture and size differences of plasmid pSCL4 between F613-1 and ATCC 27064 suggest the pSCL4 plasmid evolving from pSCL4-like and pSCL2-like extrachromosomal replicons, in addition to the previously proposed ATCC 27064 mega-plasmid formation hypothesis through recombination between the smaller F613-1 pSCL4 plasmid arm regions and the linear chromosome. Comparative genomics systemically investigate secondary metabolism capacitates in this study indicates that frequent exchange of genetic materials between Streptomyces replicons may shape remarkable diversities of secondary metabolite repertoires. Consequently, the F613-1 strain seems to have evolved its specific genomic architectures and genetic patterns to meet the requirement in subsequent industrial processes.